The San Francisco division of the FBI swooped in on a handful of East Bay communities in a series of drug busts targeting a Mexican drug cartel.

Arrests and search warrants were executed Tuesday in Pittsburg, Antioch, Oakley and Concord.

Special agents with the FBI combed through a home in the 900 block of Carpino Way in Pittsburg. Vehicles parked out front were looked at in search of hidden compartments that could be used to transport drugs.

A short time later, a K-9 unit with the Danville Police Department sniffed for traces of illegal substances. It was all part of an early morning sweep conducted by the FBI to disrupt the flow of drugs involving a Mexican cartel.

"I knew the lady that lived in that house all my life growing up, and to know now that her home is overtaken by that sort of element is hurtful,” said Yolanda Braggs, who works at Little People’s Day Care in Pittsburg.

"It was a necessity,” FBI Special Agent Peter Lee said. “We thought that the timeline right now for this investigation, the execution of the arrest and search warrants needed to happen today."

Starting at around 6 a.m. Tuesday morning, agents with the FBI and Drug Enforcement Administration, along with support from the Contra Costa County Sheriff's Department and local police, executed six arrests and search warrants in six locations in Pittsburg, Antioch, Oakley and Concord.

"These individuals in connection with this case were considered armed and dangerous,” Lee said. “They also had drugs associated with them as well, so again, when we deal with these sorts of gangs and organized crime, we have to consider them armed and dangerous."

"You always see the cars and what not, but you never really think anything about it,” neighbor Dennis Evans said. “But I didn't think anything quite that serious was going on."